1. Field of the Invention
The present invention relates to an image output system, an image forming apparatus, and an image forming operation program. More particularly, it relates a technology to prevent unauthorized output of image data.
2. Description of the Related Art
In recent years, leakage of confidential information due to unfair outputting of a confidential document and taking out the same to outside is a big problem in companies and the like. A technology for preventing such output and taking-out of a confidential document has been strongly desired.
As technologies for preventing output and taking-out of the confidential document, there have been proposed a technology of applying a pattern processing to image data to be outputted as disclosed in Japanese Patent Unexamined Publication No. 2005-94327, a technology of embedding copyguard information as electronic watermark information to image data to be outputted as disclosed in Japanese Patent Unexamined Publication No. 2004-274092, and a technology of embedding information, indicating output date information and information associated with a personal computer and a printer, as electronic watermark information into a background image as disclosed in Japanese Patent Unexamined Publication No. 2006-60805.